scholarly journals Case Study on the 20 Years Propagation of Carbonation in Existing Concrete Facades and Balconies

2019 ◽  
Vol 60 (1) ◽  
pp. 1-12
Author(s):  
Jukka Lahdensivu ◽  
Elina Lahdensivu ◽  
Arto Köliö
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Field Measurements ◽  
Time Interval ◽  
Initiation Phase ◽  
Root Model ◽  
1960S And 1970S ◽  
The 1960S ◽  
First Time

Abstract In the most service life models of reinforced concrete structures the initiation phase is the most crucial, because according to models, service life of the structure will end underestimation on conservative side when carbonation achieves the reinforcement for the first time. The square root model is widely used in predicting carbonation depth of reinforced concrete. The model is based on diffusion laws and thereby arguable for inhomogeneous concrete. The model was evaluated by field measurements from one existing concrete building by conducting condition investigation twice at a time interval of 20 years. Samples were taken from exposed aggregate concrete sandwich panels and balcony side panels. Compared to the data collected from large number of buildings, the measured carbonation rates were very common for Finnish concrete buildings made during the 1960s and 1970s. According to this study, in solid concrete the progress of carbonation of concrete can be predicted reliably with Fick’s second law. This model, however, gives too pessimistic predictions for concrete suffering from freeze-thaw damage. Therefore, a new model has been presented for damaged concrete.

Comparative Assessment of Rule-Based Design on the Pressures and Resulting Scantlings of High Speed Powercrafts

2020 ◽  
Author(s):  
Jean-Baptiste R.G. Souppez ◽  
Ermina Begovic ◽  
Pradeep Sensharma ◽  
Fuhua Wang ◽  
Anders Rosén
Keyword(s):  
High Speed ◽  
Future Trends ◽  
Rule Based ◽  
Marine Vehicles ◽  
Current State ◽  
Regulatory Bodies ◽  
1960S And 1970S ◽  
The 1960S ◽  
Design Case Study

The rules and regulations inherent to the design pressures and scantlings of high-speed powercrafts are numerous, and regularly reviewed. Recently, the new ISO 12215-5:2019 made notable changes to the way high-speed crafts are analysed, including extending the acceleration experienced up to 8 g in certain circumstances. Nevertheless, despite the multiple iterations and variety of regulatory bodies, the seminal work undertaken on planing crafts throughout the 1960s and 1970s remains the foundation of any rule-based design requirement. Consequently, this paper investigates an array of recently published rules though a comparative design case study, the current state-of-the-art across a number of regulations, and the ultimate impact on scantlings. The study reveals that, despite divergence in intermediate calculations and assumptions, similar requirements are ultimately achieved. Eventually, discussion on the comparison undertaken and future trends in high-speed marine vehicles is provided, tackling the relevance of classical planing theory in light of contemporary innovations.

scholarly journals New and rare species of Volvocaceae (Chlorophyta) in the Polish phycoflora

2013 ◽  
Vol 82 (4) ◽  
pp. 259-266 ◽  
Author(s):  
Ewa A. Dembowska
Keyword(s):  
Rare Species ◽  
Light Microscope ◽  
Aquatic Ecosystems ◽  
Oxbow Lakes ◽  
Vistula River ◽  
Photographic Documentation ◽  
Pandorina Morum ◽  
1960S And 1970S ◽  
The 1960S ◽  
First Time

Seven species of Volvocaceae were recorded in the lower Vistula River and its oxbow lakes, including <em>Pleodorina californica</em> for the first time in Poland. Three species – <em>Eudorina cylindrica</em>, <em>E. illinoisensis</em> and <em>E. unicocca</em> – were found in the Polish Vistula River in the 1960s and 1970s, as well as at present. They are rare species in the Polish aquatic ecosystems. Three species are common both in the oxbow lakes and in the Vistula River: <em>Eudorina elegans</em>, <em>Pandorina morum</em> and <em>Volvox aureus</em>. New and rare Volvocaceae species were described in terms of morphology and ecology; also photographic documentation (light microscope microphotographs) was completed.

Reshaping Public Intellectual Life: Frank Moorhouse and His Milieu

2015 ◽  
Vol 156 (1) ◽  
pp. 133-141
Author(s):  
Catharine Lumby
Keyword(s):  
Moral Values ◽  
Public Intellectual ◽  
Public Intellectuals ◽  
Intellectual Life ◽  
Writing Practices ◽  
1960S And 1970S ◽  
The 1960S ◽  
Fiction Writer ◽  
The Way

This article uses Frank Moorhouse as a study of the formation of a public intellectual in the 1960s and 1970s. Moorhouse was a key figure in the Sydney Push, a loose Libertarian-anarchist network of artists, writers, intellectuals and party people who rejected the dominant moral values of the 1950s and 1960s. A journalist, Moorhouse later became a well-known fiction writer who was part of a similarly bohemian and activist milieu centred in Sydney's Balmain. Taking Frank Moorhouse as a case study, I will argue that there is something particular about the way public intellectuals have historically been formed and given voice in Australian life, which is characterised by a permeability between art and writing practices and between academic and activist milieux.

scholarly journals Long-Term Performance of Trestle Bridges: Case Study of an Indonesian Marine Port Structure

2020 ◽  
Vol 8 (5) ◽  
pp. 358 ◽  
Author(s):  
Yusak Oktavianus ◽  
Massoud Sofi ◽  
Elisa Lumantarna ◽  
Gideon Kusuma ◽  
Colin Duffield
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
Service Life ◽  
Field Measurement ◽  
Field Measurements ◽  
Element Analysis ◽  
Moment Capacity ◽  
Non Destructive

A precast reinforced concrete (RC) T-beam located in seaport Terminal Peti Kemas (TPS) Surabaya built in 1984 is used as a case study to test the accuracy of non-destructive test techniques against more traditional bridge evaluation tools. This bridge is mainly used to connect the berth in Lamong gulf and the port in Java Island for the logistic purposes. The bridge was retrofitted 26 years into its life by adding two strips of carbon fiber reinforced polymer (CFRP) due to excessive cracks observed in the beams. Non-destructive field measurements were compared against a detailed finite element analysis of the structure to predict the performance of the girder in terms of deflection and moment capacity before and after the retrofitting work. The analysis was also used to predict the long-term deflections of the structure due to creep, crack distribution, and the ultimate moment capacity of the individual girder. Moreover, the finite element analysis was used to predict the deflection behavior of the overall bridge due to vehicle loading. Good agreement was obtained between the field measurement and the analytical study. A new service life of the structure considering the corrosion and new vehicle demand is carried out based on field measurement using non-destructive testing. Not only are the specific results beneficial for the Indonesian port authority as the stakeholder to manage this structure, but the approach detailed also paves the way for more efficient evaluation of bridges more generally over their service life.

scholarly journals Late-20th-century changes in glacier extent in the Caucasus Mountains, Russia/Georgia

2006 ◽  
Vol 52 (176) ◽  
pp. 99-109 ◽  
Author(s):  
Chris R. Stokes ◽  
Stephen D. Gurney ◽  
Maria Shahgedanova ◽  
Victor Popovnin
Keyword(s):  
Field Measurements ◽  
Thematic Mapper ◽  
Ice Age ◽  
Late 20Th Century ◽  
The Caucasus ◽  
Central Caucasus ◽  
Caucasus Mountains ◽  
1960S And 1970S ◽  
Colour Composite ◽  
The 1960S

AbstractGlaciers occupy an area of ~1600km2 in the Caucasus Mountains. There is widespread evidence of retreat since the Little Ice Age, but an up-to-date regional assessment of glacier change is lacking. In this paper, satellite imagery (Landsat Thematic Mapper and Enhanced Thematic Mapper Plus) is used to obtain the terminus position of 113 glaciers in the central Caucasus in 1985 and 2000, using a manual delineation process based on a false-colour composite (bands 5, 4, 3). Measurements reveal that 94% of the glaciers have retreated, 4% exhibited no overall change and 2% advanced. The mean retreat rate equates to ~8ma–1, and maximum retreat rates approach ~38 m a–1. The largest (>10 km2) glaciers retreated twice as much (~12ma–1) as the smallest (<1 km2) glaciers (~6ma–1), and glaciers at lower elevations generally retreated greater distances. Supraglacial debris cover has increased in association with glacier retreat, and the surface area of bare ice has reduced by ~10% between 1985 and 2000. Results are compared to declassified Corona imagery from the 1960s and 1970s and detailed field measurements and mass-balance data for Djankuat glacier, central Caucasus. It is concluded that the decrease in glacier area appears to be primarily driven by increasing temperatures since the 1970s and especially since the mid-1990s. Continued retreat could lead to considerable changes in glacier runoff, with implications for regional water resources.

“Deplorable Exegesis”: Dick Gregory's Irreverent Scriptural Authority in the 1960s and 1970s

2020 ◽  
Vol 30 (2) ◽  
pp. 187-236
Author(s):  
Vaughn A. Booker
Keyword(s):  
African American ◽  
Religious Belief ◽  
Jim Crow ◽  
Religious Writings ◽  
Religious Liberalism ◽  
History Of ◽  
1960S And 1970S ◽  
The 1960S ◽  
Social Teachings

ABSTRACTThis article examines comedian Richard Claxton “Dick” Gregory's comical articulation of religious belief and belonging through his speeches and religious writings during the 1960s and 1970s. It argues that, during his most visible public presence as an activist and comedic entertainer, Gregory bore an irreverent scriptural authority for his readers and comedy audiences who sought a prominent, public affirmation of their suspicion and criticism of religious authorities and conventional religious teachings. This suspicion would allow them to grapple with the oppressive presence of religion in the long history of Western colonialism, in the U.S. context of slavery, and in the violence and segregation of Jim Crow America. Following this religious suspicion, however, Gregory's consistent goal was to implement just social teachings stemming from socially and theologically progressive readings of the Hebrew Bible and of the teachings of Jesus in the Gospels. Gregory's irreverence modeled, and reflected, the maintenance of belief in both the divine and in the justness of remaking an oppressive, violent, unequal world through nonviolent activism in accordance with his understanding of the teachings of the King James scriptures that he read throughout his life. This study of comedy uses one African American male's production of irreverent, authoritative religious rhetoric to display a noteworthy mode of mid-century African American religious liberalism. It is also a case study highlighting the complexity of religious belief and affiliation. Despite acknowledged ambivalences about his commitments to religion, Gregory also modeled ways for audiences to reframe religious commitments to produce social change.

A Geopolitical Economy of Heavy Industrialization and Second Tier City Growth in South Korea: Evidence from the ‘Four Core Plants Plan’

2017 ◽  
Vol 44 (3) ◽  
pp. 405-420 ◽  
Author(s):  
Young-Jin Choi ◽  
Jim Glassman
Keyword(s):  
South Korea ◽  
Developmental State ◽  
Korean Economy ◽  
Us Military ◽  
Original Plan ◽  
Second Tier ◽  
1960S And 1970S ◽  
The 1960S ◽  
The City

In this article, we examine heavy industrialization and second tier urbanization in South Korea during the 1970s from a geopolitical economic perspective. We highlight the crucial, spatially complex geopolitical process of forming transnational class alliances, embedded in Cold War geopolitics, which has been neglected within state-centric developmental state theories and approaches to urbanization. Specifically, we trace the changes in the state’s original developmental plan for promoting the machinery industry in the southeast region during the 1960s and 1970s. We show how Hyundai, one of the most dominant chaebols, grew to exercise decisive influence over the state’s developmental strategy and became a powerhouse in the Korean economy, particularly in the city of Ulsan. Based on a case study of the Four Core Plants Plan, we show that the success of Hyundai was not an outcome of the effectiveness of the state’s developmental policy but was, ironically, due to the failure of the government’s original plan. The successful substitution of Hyundai’s own strategy for the state’s plan, which contributed enormously to the growth of Ulsan, would have been impossible without Hyundai’s enrollment into the transnational geopolitical economic alliance spurred by US military projects in Asia.

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